Can under-baseboard point rodding have a kink to pass under cutaways?

[Lacathedrale]

I'm looking to use slide switches and push/pull rods for turnouts under a layout, but at the front of the layout I was planning to include a canal which will obviously be below the level of the track.

 

Can I introduce a pair of  45 degree kinks into the turnout control rodding for it to pass under the canal at the front of the layout, but rise up to the roadbed on the rear without introducing mechanical issues, as long as both sides are in guide tubes?

 

Seems reasonable to me - but I think if it's going to be a problem I'd just fill in the canal! I know that I can probably use wire-in-tube or servos, but given the choice I'd like to use what I have to hand.

[Talltim]

You may end up with the rod flexing a bit, it depends how bendy the rod is and how much tolerance your point can cope with. If you could support the rod with tube below the canal it might work better.

===     ===
   \===/
   
Rather than
===     ===
   \___/

(Where = is rod in tube) Edited November 29, 2018 by Talltim

[Titan]

You may have issues with the rod bending. However if you want a Rolls Royce rod solution, you could fabricate a pair of levers with a pivot in the middle. You put them vertically, one each side of the canal, so the bottom of each lever is just under the canal, and the top level with your operating rod and points. You will need three short rods. One to connect the bottom of the levers together, one from the top of a lever to the points, and the control rod.

 

Something like this, with the pivot in the middle of the  levers ( the gap between the \)

 

____  canal ____ operating rod

 lever\  |__|  \  lever

          \_____\  

      operating rod

Edited November 29, 2018 by Titan

[Lacathedrale]

The canal will be right up against the front edge of the layout, so no need for it to rise back up

  |
==|==============
  `---(    )--   |
              \  |=================
               \----(     )---###--|--O

Where (   ) are the tubes,  ### is the slide switch and 'o' is the handle on the front of the wire.

 

I guess if I make sure to include a join after the first tube (using something like a single chocolate block connector) then I could always retrofit other methods, right?

[Dunsignalling]

The critical thing with wire-in-tube control of points is that the wire has a natural inclination to wander about, leading to lost movement at the business end. The tube must be fixed firmly enough to stop that happening, whilst not hampering the push/pull action of the wire.  

 

If using rods and pivots, the important things are the rigidity (or otherwise) of the rods, and the amount of slack in the pivots. The greater the number of pivots, the more movement will be lost.

 

However, in a relatively short run, incorporating a couple of cranks to take the drive under your canal should be easily achievable with a bit of trial and error.

 

John

Edited November 29, 2018 by Dunsignalling

[Campaman]

I have done a similar thing with cranked rodding and its working fine.

 

I don't have it in tube though, I create a trough for it to run in by fixing thin pieces of wood either side of the rods, that way you can shape a piece to suit your crank so its supported either side and can not flex in that direction.

[Lacathedrale]

Ah, so definitely using cranks or wire-in-tube rather than rod-with-bends?

[Enterprisingwestern]

On my plank I have a couple of points with two 45 degree bends in the plastic tube and wire operating mechanism. the route is carved out of the cork sub base and the plastic is a tight fit in the resulting slot, but I have flooded the route with PVA just to make sure they don't wander.

It's easy to tell which two they are by the considerable extra resistance.

 

Mike.

[Lacathedrale]

Right well I'm not actually hoping to have to do wire and tube, but I'm glad it works too.

[RailWest]

Looking at your post No 4, am I right to assume that you propose to pass the linkage below the bed of the canal? 

 

If so, then allowing for the depth of the (fake) water in the canal above that, and the fact is often rather muddy and not easier to see into, might you not be able to extend the bottom of the lever at the LH a bit further downwards so that the rodding can run on the level in a tube through the 'water'? 

[Campaman]

My rods are actually bent, no cranks as such, just supported either side so they stay in line.

[34theletterbetweenB&D]

Although you can engineer your way around bends in push rods, 'KISS' rules, use a straight rod if possible.

 

Who says the rod has to be horizontal? Small deviations won't cause any problems. Start the rod low enough at the board edge to clear under the canal (or concealed below the surface of opaque water per RailWest's good suggestion) and you are done.

[KeithHC]

Or you could model a gas main or water main that crosses the canal.

 

Keith

[luckymucklebackit]

Another solution (if room permits) would be to solder  brass webs in place on the upright sections, these would prevent bending.

 

Jim

[sharris]

The canal will be right up against the front edge of the layout, so no need for it to rise back up

  |
==|==============
  `---(    )--   |
              \  |=================
               \----(     )---###--|--O

Where (   ) are the tubes,  ### is the slide switch and 'o' is the handle on the front of the wire.

 

I guess if I make sure to include a join after the first tube (using something like a single chocolate block connector) then I could always retrofit other methods, right?

 

You might want to either put a notice on the handle, or introduce a second horizontal lever, since the single lever will reverse the sense of the control relative to any without levers (i.e. pulling the handle will push the point-blades, and vice versa). 

[long island jack]

Depend on the width of the layout, you could use bike spokes bent to fit, there usually 12" long

 

 

 

Ray

[Oldddudders]

In days of olde, we were recommended to include an omega loop in the drive from the motor to the point. It buffered the abrupt action of the motor, protecting the tie-bar. What the OP is seeking is not too different.

[Lacathedrale]

Thank you all for the excellent thoughts and ideas - I'm trying to avoid extra complexity wherever I can so no cams/extra pivots if possible. My thoughts on using a pair of 45' bends rather than a pair of 90' bends was simply to try and reduce the amount of flex. I think if I can make it happen then a shallow angle all the way from the front of the layout to a retaining bracket just after a kink would be the best option.  As per Ian's comment above however, do I need to include omega loops as opposed to adjusting the grip of the retaining bolts on the slide switch?

[Oldddudders]

I suspect it unnecessary, since your action will be less snappy than a solenoid motor.

[37114]

I used Omega loops on Peafore Yard as well as leaving a section of wire not in the tube to allow some flex. I used slide switches to both latch the handbuilt points and do the polarity. The throw on the switch was slightly more than the points so the flex took up the pressure, in 4 years of exhibiting it I never had a point failure. I also used a crank to move the point on the upper level, there are some photos on the layout thread and the point control was also featured in a BRM video (December 2016 I recall)

Edited December 12, 2018 by 37114

[Enterprisingwestern]

 As per Ian's comment above however, do I need to include omega loops as opposed to adjusting the grip of the retaining bolts on the slide switch?

 

There is no need for omega loops with slide switches, just drill a series of holes horizontally in the black plastic bit and make a slot which co-incides with the ends of the point blade deflection.

 

Mike.

[Right Away]

Providing the rod is supported loosely before and after any deviation (double set/right angle) it will work.

A pair of strip connectors - similar to that in Ray's photo above, screwed to the bottom of the baseboard and passing the rod through one side has stabilised my rodding for some years. Fine tune the action by gently adjusting the terminal screws. It would be advantageous to minimize the vertical drop as much as possible.

[KalKat]

There is the possibility of using R/C control 'snake' . It's a lot  less frictional than wire in tube and a lot more flexible/easier to use.

 

 

 

Emma

[Lacathedrale]

There is the possibility of using R/C control 'snake' . It's a lot  less frictional than wire in tube and a lot more flexible/easier to use.

 

 

 

Emma

 

Hi there, I assumed that wire-in tube and RC control snakes were the same thing - do you have an example/link I can see?